Despite the greater capacity of peripheral as compared to central neurons to regenerate, the auditory nerve does not show spontaneous regenerative capacity (Starr et al. (2004) J Assoc Res Otolaryngol 5:411-426; White et al. (2000) Hear Res 141:12-18; McFadden et al. (2004) Brain Res 997:40-51; Kujawa and Liberman (2009) J Neurosci 29:14077-14085). The loss of afferent innervation of hair cells can result from retraction of peripheral fibers after noise damage or from complete loss of neurons (White et al. (2000) Hear Res 141:12-18). Methods of promoting reinnervation of hair cells would therefore be important for the treatment of hearing loss.